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Ca + H₃PO₄ → Ca₃(PO₄)₂ + H₂
Balance PO₄.
1 on the left, 2 on the right. Add a coefficient of 2 in front of H₃PO₄.
Ca + 2H₃PO₄ → Ca₃(PO₄)₂ + H₂
Balance H.
6 on the left, 2 on the right. Add a coefficient of 3 in front of H₂.
Ca + 2H₃PO₄ → Ca₃(PO₄)₂ + 3H₂
Balance Ca.
1 on the right, 3 on the right. Add a coefficient of 3 in front of Ca.
3Ca + 2H₃PO₄ → Ca₃(PO₄)₂ + 3H₂
Our final balanced equation:
3Ca + 2H₃PO₄ → Ca₃(PO₄)₂ + 3H₂
Hope this helps!
Answer:
Lichens can be used as air pollution indicators, especially of the concentration of sulphur dioxide in the atmosphere. Lichens are organisms that grow in exposed places such as rocks or tree bark. They need to be very efficient at absorbing water and nutrients to grow there.
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The percentage of the family’s total annual electricity that is used to run the two air conditioners for the three summer months = 19.4 %</h2>
Explanation:
Average electricity consumed per month = 900 kWh
The family cools their house for three months during the summer with two window-unit air conditioners
The power consumed by one window-unit air conditioners = 350 kWh
The power consumed by two window-unit air conditioners = 350(2) = 700 kWh
Power consumed for two air conditioners for the three summer months = 700 (3) = 2100 kWh
Total power consumed for 1 year = 900 (12) = 10800kWh
The percentage of the family’s total annual electricity that is used to run the two air conditioners for the three summer months = 
= 19.4 %
Answer: A chemical process must occur and then changes between the state of the reactants and the state of the products can be determined
Explanation: Enthalpy represents the sum of the energy of the system with the product of the pressure and volume of that system. As a thermodynamic property, it expresses the ability to release heat from the system. In fact, enthalpy tells us how much heat and work has changed during the chemical reaction under constant pressure. When measuring, measurements of the difference in enthalpy between the two states of the system is performed, before and after the chemical reaction, since total enthalpy can not be measured. This measurement of the enthalpy change can tell us, for example, whether the heat was released from the system during the reaction, or the system absorbed the heat.
Answer:
closer to F because fluorine has a higher electronegativity than carbon
Explanation:
Electronegativity refers to the ability of an atom in a bonding situation to draw the shared electrons of the bond closer to itself.
Electronegativity increases across the period and decreases down the group. A highly electronegative atom draws the shared electron pair of a bond towards itself.
When two atoms are bonded together, the electron pair is always drawn closer to the atom that has a higher electronegativity.
Hence, the electron pair in a C-F bond could be considered closer to F because fluorine has a higher electronegativity than carbon.
